mellin



(No Model.) 2 Sheets-Sheet 1.

G. J. MELLIN. COMPOUND STEAM ENGINE.

No. 536,639. Patented Apr. 2,1895.

\V//A V/ lNVENTEI R- WITNESSES (No Model.) 2 Sheets-Sheet 2.

a. JQMELLIN.

COMPOUND STEAM ENGINE. I v 1 Patented Apr. 22,1895,

a -Ma W ITNES SES. INVENTDR- UNITED STATES PATENT Games;

CARL J. MELLIN, OF RIOHMON D, VIRGINIA, ASSIGNOR TO THE RICHMOND LOCOMOTIVE AND MACHINE WORKS, OF SAME PLACE.

COMPOUND STEAM-ENGINE.

SPECIFICATION forming part of Letters Patent No. 536,639, dated April 2, 1895. Application filed March 19, 1894. Serial No, 504,179. (No model.)

To all whom it may concern:

Be it known that I, CARL J. MELLIN, a citizen of the United States, and a resident. of

' Richmond, in the county of Henrico and State of Virginia, have invented certain new and useful Improvements in Compound Steam-Engines, of which the following is a specification.

My invention relates to intercepting valves for temporarily working high steam direct in both cylinders of a compound engine at starting, and to emergency valves, whereby the direct action of the live steam maybe continued longer in the low pressure cylinder at starting, and the change from compound to direct action may be readily effected while working, as often required in the case of a locomotive engine on steep grades.

The invention consists of the hereinafter described improvements in the intercepting and emergency valves reference being had to the accompanying drawings, in which Figure 1, is a horizontal longitudinal sectional elevation of the intercepting and emergency valves as arranged when located in the smoke box of a locomotive engine the valves being in positions for the normal compound operation, the section being taken on line m0a Fig. 2. Fig. 2, is an end elevation of the smoke box of a locomotive with the cover removed and showing a side elevation of the intercepting and emergency valves as therein applied, the scale of the drawing being considerably reduced as compared with Fig. 1 Fig. 3, is a longitudinal sectional elevation of the said valves in a modified arrangement, the valves being in the positions for compound operation, and Fig. 4, is a detail of the apparatus of Fig. 3, with the valves in the positions for working live steam directly in both cylinders.

Referring to Fig. 2, (1 represents the shell of the smoke box of a locomotive engine; I) and c, the receiver of the exhaust steam from the high pressure cylinder; cl, the case of the intercepting valve; e, the case of the emergency valve, and fthe pipe making communication between valve case d and the low press-,

ure cylinder. From the receiverb-c the exhaust steam from the high pressure cylinder enters the chamber 9 of the intercepting valve case, from which the intercepting valve h admits it to pipe f when working in the compound system, said valve h then being open as in Figs. 1 and 3, the pressure of the exhaust steam on the said valve hbeing the means of opening it.

The valve h is carried by the stem '6, working in the sleeve j, and by the piston working in the dash pot Z. The sleeve j reciprocates in the cover m of valve case 01. It has a shoulder 11. always subject to live steam pressure in chamber 0, admitted thereto through pipe 19 whenever the throttle valve is open. The inner end q of this sleeve bears against the shoulder s of valve h. The outer end is open to the atmosphere. It will be seen that on opening the throttle valve to start the engine live steam at once entering the chamber 0, and acting on shoulder n, in advance of any pressure of exhaust steam in chamber 9 from the high pressure cylinder, will automatically close valve h, and open passage for itself into the low pressure cylinder by forcing sleeve j, so far that shoulder n, escapes from the bore 25, in which the enlarged end of said sleeve works, as shown in Fig. 4, thus enabling high pressure steam to act in both cylinders for starting.

At the side of chamber g, opposite to valve h, said valve has a piston it, working in a dash pot 1, which serves in such case'to prevent the valve h from being closed with a shock, besides also'serving as a guide to the said valve. The piston also serves as a valve to control theexhaust in emergency cases as will appear farther on. When after a turn or a turn and ahalf ofthe engine, pressure of exhaust steam from the high pressure cylinder accumulates in chamber g, it overbalances the pressure of live steam on the other side of valve h which is limited because of the limited quantity that can escape through the sm all bore t, and which decreases as the speed of the engine increases, and thus automatically opens valve h, and thereafter the engine operates by the compound system.

The emergency valve is shown at 11., Figs. 1 and'2, and u, Figs. 3 and t. Its purpose is to open a direct passage for the escape of the exhaust steam of the high pressure cylinder from'chamber g, whereby valveh may remain closed and live steam may be used di-' rectly in both cylinders any desired length of time after starting, or the change from compound to direct action may be effected at any time while running, said emergency valve being adapted to be opened at the will of the engineer in any approved way, as by steam admitted behind the piston e or 1; through a small pipe to to be controlled by a cook or valve at the engineers station. The coiled spring a closes this emergency valve when steam is shut off from behind piston 11 or v. The steam thus exhausting from chamber 9 escapes through the ports I) in the cylinder 0' of the dashpot and thence along the cored passage (1 in Fig. 1, to the valve 11., from which it issues at 6' into the emergency exhaust pipe f which discharges in the locality of the usual exhaust nozzle of thelocomotive engine; it may be into the low pressure exhaust passage when convenient. In Figs. 3 and 4, the passage of the exhaust steam of the emergency valve is through ports g and it issues therefrom at (2 to the exhaust pipe f which is also adapted for discharge in the locality of the principal exhaust nozzle when used in a locomotive engine, or into the low pressure exhaust passage. It is to be noted that valve h enters the recess a of its seat and practi cally closes communication between the low and high pressure sides at or a little before shoulder at. issues from cylinder 25, and thereby prevents any waste of live steam through the emergency exhaust, and said valve 7t, also closes at or slightly before piston It, opens 6X,

haust through ports b'as a further means of preventing such waste.

In Figs. 1 and 2 the combined case for the two valves has an extension lb of the end having the openings for receiving the valves projecting outward through the shell a,'of the fire box, with a flange t" suitably shaped to lit and be secured to the inside of the shell, so that cover m, of the intercepting valve case d, and the coverj' of the emergency valve case e, are both accessible outside of said shell, and the cover m, contains the sleeve j, and the steam way 0 for admitting live steam to said sleeve and to the low pressure cylinder, and the cover of the emergency valve case carries the lantern bush k of the valve u forming a seat for the valve, which together with the valve is removable with the cover. The cylinder 0 of the dash pot is also a lantern bush of the cover n of the inner end of the valve case at, and is thereby removable with said cover, this being the case when the valve is placed in the smoke box only, but if placed in the cylinder saddle as intended to be in some cases, it will be removable at one end of the saddle.

In Figs. 3 and 4, the dash-pot cylinder is part of a duplex lantern bush 0' 0 the part a being intermediate of the part c, and the cover 11. and being of larger diameter to receive the bush of the chamber of the emergency valve which in this arrangement is placed in the same line with theintercepting ssaeae valve, but is alike removable independently of the intercepting valve. The bush 7& has a steam tight ball joint in at the inner end with the part c of the duplex daslrpot bush, and said part c has a like ball or other approved joint m with the case to prevent leak of steam past the emergency valve.

I am aware that intercepting and emergency valves are not new broadly and I do not so claim them.

I claim as my invention-*- 1. In a compound engine having the intercepting valve in the steam passage between the high and low pressure cylinders adapted to be normally held open by the pressure of exhaust steam from the high pressure cylinder, and provided with means for direct action ofthe live steam to close it in the absence of the exhaust steam, said engine also having the emergency valve for relieving the intercepting valve of the pressure of said exhaust steam from the high pressure cylinder, the combination with said intercepting and emergency valves of the dash-pot for checking the intercepting valve located intermediately of said intercepting and emergency valves substantially as described.

2. In a compound engine having the intercepting valve in the steam passage between the high and low pressure cylinders adapted to be normally held open by the pressure of exhaust steam from the high pressure cylinder and provided with means for direct action of the steam to close it in the absence of the exhaust steam, said engine also having the emergency valve for relieving the inter: cepting valve of the pressure of said exhaust steam from the high pressure cylinder, the combination with said intercepting and emergency valves of the dash-pot located intermediately of said valves and forming a cushion for the intercepting valve after opening the emergencyexhaust substantially as described.

3. In a compound engine having the inter- =cepting valve in the steam passage between the high and low pressure cylinders adapted to be normally held open by the pressure of the exhaust steam from the high pressure cylinder and provided with means for direct action of the steam to closeit in the absence of the said exhaust steam, said engine also having the emergency valve for relieving the intercepting valve of the pressure of the said exhaust steam from the high pressure cylinder, the combination with said intercepting and emergency valves, of the daslrpot located intermediately of said valves, said intercepting valve adapted to close at or before the opening of the exhaust substantially as described.

4. In a compound locomotive,the combination of the intercepting valve in the steam receiver between the high and low pressure cylinders, and adapted to be normally held open by the steam exhausting from the high pressure cylinder into the low pressure cylinder, means to close said intercepting valve IIO by live steam, and admit the said live steam into the low pressure cylinder in the absence of pressure of exhaust steam on the opening side of said intercepting valve, and the emergency valve, said emergency valve located in line with the intercepting valve and in the same case, and subject to control of the engineer substantially as described.

5. In a compound engine having the intercepting valve in the steam passage between the high and low pressure cylinders adapted to be normally held open by the pressure fot the exhaust steam from the high pressure cylinder, and provided with means for direct action of live steam to close it in the absence of the exhaust steam,said engine also having an emergency valve, the combination with said 1ntercepting valve of the dash-pot for checking the said valve in closing, said dashpot and intercepting valve located on opposite sides of the receiving chamber respectively, each accessible independently of the other, and said dash-pot located intermediately of the intercepting and emergency valves substantially as described.

6. In a compound engine having the intercepting valve in the steam passage between the high and low pressure cylinders adapted to be normally held open by the, pressure of the exhaust steam from the high pressure cylinder, and provided with means for direct action of live steam to close it in the absence of said exhaust steam, said engine also havin g an emergency valve, the combination with the valve case of the dash-pot for checking the said intercepting valve in closing, said valve and dash-pot located on opposite sides of the receiving chamber respectively, each accessible independently of the other, said dash-pot located intermediately of the intercepting and emergency valves, and the cylinder of the dash-pot formed on and being removable with the cover of the end of the valve case substantially as described.

7. In a compound engine having the intercepting valve in the steam passage between the high and low pressure cylinders adapted to be normally held open by the pressure of the exhaust steam from the high pressure cylinder, and provided with means for direct action of the steam to close it in the absence of said exhaust steam, said engine also having the emergency valve for relieving the intercepting valve of the pressure of said exhaust from the high pressure cylinder, the combination with the valve case of the said intercepting and emergency valves separately and independently applied in a single case common to both and removable from the said case separately substantially as described.

8. In a compound engine having the intercepting valve in the steam passage between the high and low pressure cylinders adapted to be normally held open by the pressure of the exhaust steam from the high pressure cylinder, and provided with means for direct action of the steam to close it in the absence of said exhaust steam, said engine also having the emergency valve for relieving the intercepting valve of the pressure of said exhaust from the high pressure cylinder, the combination with the valve case of the said intercepting and emergency valves separately and independently applied to the ends of the case respectively, and separately removable from the case substantially as described.

9. In a compound engine having the intercepting valve in the steam passage between the high and low pressure cylinders adapted to be normally held open by the pressure of the exhaust steam from the high pressure cylinder and provided with means for direct action of the steam to close it in the absence of said exhaust steam, said engine also having the emergency valve for relieving the intercepting valve of the pressure of said exhaust from the high pressure cylinder, the combination with the valve case of said emergency valve fitted in a bush attached to the cover of the end of the case substantially as described.

10. In a compound engine having the intercepting valve in the steam passage between the high and low pressure cylinders adapted to be normally held open by the pressure of the exhaust steam from the high pressure cylinder and provided with means for direct action of the steam to close it in the absence of said exhaust steam, said engine also having the emergency valve for relieving the intercepting valve of the pressure of said exhaust from the high pressure cylinder, a duplexlantern bush having the dash-pot for checking the motion of the intercepting valve, and the emergency valve also fitted in the said duplex lantern bush substantially as described.

11. In a compound locomotive engine having the intercepting valve in the steam passage between the high and low pressure cylinders adapted to be normally held open by the pressure of the exhaust steam from the high pressure cylinder, and provided with means for direct action of the steam to close it in the absence of said exhaust steam, said engine also having the emergency valve for relieving the intercepting valve of the pressure of said exhaust from the high pressure cylinder, the valve case and said valves located in the smoke box with an outward extension of one end of the case through the shell of the box, and each independently and removably applied to the case substantially as described.

12. The combination with theintercepting valve and the emergency valve, of the dashpot located on the side of the chamber receiving the steam from the high pressure cylinder, opposite to the intercepting valve, and the piston on the end of the intercepting valve which engages the dash-pot, said piston also constituting a valve for delaying the exhaust, till the intercepting valve closes escape for the live steam substantially as described.

13. In a compound engine having the intercepting valve in the steam passage between the high and low pressure cylinders and provided with the emergency valve, said intercepting valve adapted to be normally held open by the pressure of the exhaust steam from the high pressure cylinder, and provided with means for being closed bylive steam on opening the emergency valve, the dash-pot for checking the said intercepting valve in closing located on and removable with the cover of the valve case and said emergency valve adapted to open and close the communication between the exhaust passage of the high pressure cylinder and the atmosphere at the will of the engineer.

14. In aeompound engine having the intercepting valve in the steam passage between the high and low pressure cylinders and provided with the emergency valve, said intercepting valve adapted to be normally held open by the pressure of the exhaust steam from the high pressure cylinder, and provided with means for being closed by live steam on opening the emergency valve, the dash-pot for checking said intercepting valve in closing located on the opening side of the intercepting valve, and said emergency valve adapted to open and close the communication between the exhaust passage of the high pressure cylinder and the atmosphere at the Will of the engineer.

Signed at Richmond in the county of Henl'ico and State of Virginia, this 3d day of March, A. D. 1894.

CARL J. MELLIN.

Witnesses:

P. F. GREENWOOD, A. L. STRATFORD. 

